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Need help identifying zener diodes

K

KenB123

Jan 1, 1970
0
Hi...

I've got two diodes that need replacing, which I think they are zeners. I
don't have a schematic.

One is marked C33PH and the other B8V2PH. Google search results turns up
references to "marking codes" and zeners, but I can't find any data.

These are in a Philips 27PT6441/37 TV set, and are marked as "6001" and
"6006" on the chassis.

Any help identifying these would be muchly appreciated.

Ken
 
L

Leonard Caillouet

Jan 1, 1970
0
I don' see a part in the parts list for that set with the location number
6006, but if it is a zener it is likely 8.2v. The 6001 diode is a 33v
zener.

Leonard
 
F

Franc Zabkar

Jan 1, 1970
0
I've got two diodes that need replacing, which I think they are zeners. I
don't have a schematic.

One is marked C33PH and the other B8V2PH.

Here's one possibility:

BZY85B8V2 8.2V 1W (PH = Philips)

The C33 looks like a 33V zener. The size should suggest its wattage.

Try searching for "BZ*C33" here:
http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/$$Search?OpenForm

If the C33 is a tuning reference diode, then it would probably be more
precise than an ordinary zener.
Google search results turns up
references to "marking codes" and zeners, but I can't find any data.

These are in a Philips 27PT6441/37 TV set, and are marked as "6001" and
"6006" on the chassis.

Any help identifying these would be muchly appreciated.

Ken

If it helps, your set appears to be using an L041UAA chassis.

BTW, a *lot* of people are having trouble with that chassis:
http://www.coxesroost.net/journal/2004/12/11/television-repair

- Franc Zabkar
 
K

KenB123

Jan 1, 1970
0
Franc Zabkar said:
Here's one possibility:

BZY85B8V2 8.2V 1W (PH = Philips)

The C33 looks like a 33V zener. The size should suggest its wattage.

Try searching for "BZ*C33" here:
http://nte01.nteinc.com/nte/NTExRefSemiProd.nsf/$$Search?OpenForm

If the C33 is a tuning reference diode, then it would probably be more
precise than an ordinary zener.


If it helps, your set appears to be using an L041UAA chassis.

BTW, a *lot* of people are having trouble with that chassis:
http://www.coxesroost.net/journal/2004/12/11/television-repair

- Franc Zabkar

Yes, it is that chassis. The 6006 diode is next to a capacitor marked 2006.
Odd part numbering system, huh?

And I did find many complaints about this model TV. It's probably not worth
fixing, but fixing things is sort of a hobby of mine. It was given to me for
free at a yard sale.

Thanks for all the help!

Ken
 
K

KenB123

Jan 1, 1970
0
If the C33 is a tuning reference diode, then it would probably be more
precise than an ordinary zener.

Yes, it does connect to the tuner.

Ken
 
L

Leonard Caillouet

Jan 1, 1970
0
KenB123 said:
Yes, it does connect to the tuner.

Ken

It is a 33 volt zener in the supply to the tuner and is not a very critical
value. It is not a tuning diode.

Leonard
 
F

Franc Zabkar

Jan 1, 1970
0
Yes, it does connect to the tuner.

Ken

FWIW, my Sanyo set uses a uPC574J 33V tuning voltage reference. It has
a low temperature coefficient (+/- 1mV/degC) and low dynamic
resistance (10 ohms). If your set uses a regular 33V zener (which has
a 30mV/degC tempco), then I guess the design of its AFT circuitry is
such that it can pull the channel in over a wide range of
temperatures. I haven't had to look at a tuning zener for a long time
so I don't know which approach is used most often today.

- Franc Zabkar
 
K

KenB123

Jan 1, 1970
0
Franc Zabkar said:
FWIW, my Sanyo set uses a uPC574J 33V tuning voltage reference. It has
a low temperature coefficient (+/- 1mV/degC) and low dynamic
resistance (10 ohms). If your set uses a regular 33V zener (which has
a 30mV/degC tempco), then I guess the design of its AFT circuitry is
such that it can pull the channel in over a wide range of
temperatures. I haven't had to look at a tuning zener for a long time
so I don't know which approach is used most often today.

- Franc Zabkar

SUCCESS! Since I did not have a dime invested in this TV I substituted
9-volt and 30-volt zeners found in the parts box. And it is now working!
Thanks for all the help, guys. I've got me a TV for my bedroom now, for as
long as it lasts.

Ken
 
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